Fatty acid nitroalkenes induce resistance to ischemic cardiac injury by modulating mitochondrial respiration at complex II

Redox Biol. 2016 Aug:8:1-10. doi: 10.1016/j.redox.2015.11.002. Epub 2015 Nov 17.

Abstract

Nitro-fatty acids (NO2-FA) are metabolic and inflammatory-derived electrophiles that mediate pleiotropic signaling actions. It was hypothesized that NO2-FA would impact mitochondrial redox reactions to induce tissue-protective metabolic shifts in cells. Nitro-oleic acid (OA-NO2) reversibly inhibited complex II-linked respiration in isolated rat heart mitochondria in a pH-dependent manner and suppressed superoxide formation. Nitroalkylation of Fp subunit was determined by BME capture and the site of modification by OA-NO2 defined by mass spectrometric analysis. These effects translated into reduced basal and maximal respiration and favored glycolytic metabolism in H9C2 cardiomyoblasts as assessed by extracellular H(+) and O2 flux analysis. The perfusion of NO2-FA induced acute cardioprotection in an isolated perfused heart ischemia/reperfusion (IR) model as evidenced by significantly higher rate-pressure products. Together these findings indicate that NO2-FA can promote cardioprotection by inducing a shift from respiration to glycolysis and suppressing reactive species formation in the post-ischemic interval.

Keywords: Electrophile; Inflammation; Mitochondria; Nitro-fatty acid; Nitroalkene.

MeSH terms

  • Alkenes / metabolism*
  • Alkenes / pharmacology
  • Animals
  • Cardiotonic Agents / metabolism
  • Cardiotonic Agents / pharmacology
  • Cell Line
  • Cell Respiration*
  • Electron Transport Complex II / antagonists & inhibitors
  • Electron Transport Complex II / metabolism*
  • Electron Transport Complex III / metabolism
  • Fatty Acids / metabolism*
  • Fatty Acids / pharmacology
  • Hydrogen-Ion Concentration
  • Male
  • Mitochondria, Heart / metabolism*
  • Myoblasts, Cardiac / metabolism
  • Myocardial Ischemia / metabolism*
  • Myocardial Reperfusion Injury / metabolism
  • Nitric Oxide / metabolism
  • Nitro Compounds / metabolism*
  • Nitro Compounds / pharmacology
  • Oxidation-Reduction
  • Rats
  • Superoxides / metabolism

Substances

  • Alkenes
  • Cardiotonic Agents
  • Fatty Acids
  • Nitro Compounds
  • Superoxides
  • Nitric Oxide
  • Electron Transport Complex II
  • Electron Transport Complex III